Bows have been used for many years as a weapon for hunting and target shooting. More advanced bows include cams that increase the mechanical advantage associated with the draw of the bowstring. The cams are configured to yield a decrease in draw force near full draw.
In order to cock a bow in preparation for firing the same, the string must be pulled toward a trigger assembly. Sufficient force must be exerted to bend the limbs of the bow which carry the string. Once the string is engaged by the trigger assembly, the trigger safety is activated. Then an arrow may be loaded in the crossbow with its back end in contact with the string, the trigger safety may be disengaged, and the trigger pulled to release or shoot the arrow.
The force required to cock the bow in this fashion has consistently been a problem for users. Specifically, despite the use of compound bows with cams that attach the string to the limbs, the force required to cock a typical bow often exceeds one hundred pounds. As a result, many devices have been designed to assist in the cocking of a crossbow.
The most sophisticated of these devices is an essentially automatic cocking machine which is attached to the stock of a bow and by means of a motorized rope system. In lieu of being motorized, these cocking devices can also be operated by means of a hand crank. While these automatic or hand cranked devices operate satisfactorily, they are somewhat expensive, add additional weight, and they are bulky when attached to the stock of the bow.
A more traditional and less expensive cocking system is shown, for example, in U.S. Pat. Nos. 5,243,956, 7,624,725 (Choma), and U.S. Pat. No. 8,439,024 (Barnett). In these types of systems, a connector is hooked onto the string and manually pulled until the string engages with the trigger assembly.
Due to the magnitude of the forces stored in the bow after cocking, de-cocking the bow can be difficult and hazardous.